Benign Paroxysmal Positional Vertigo (BPPV)

Benign paroxysmal positional vertigo is the most common disorder of balance. Benign paroxysmal positional vertigo is characterized by brief attacks of vertigo, with associated nystagmus, precipitated by certain changes in head position concerning gravity. It is the most common cause of the syndrome of provoked vertigo.

• Inner ear problem that results in short-lasting but severe, room-spinning vertigo.
  • Benign- not a very serious or progressive condition
  • Paroxysmal-  sudden and unpredictable in onset
  • Positional- comes with a change in head position.
  • Vertigo- causing a sense of dizziness.

Pathophysiology Of Benign Paroxysmal Positional Vertigo (BPPV)

• BPPV occurs due to the inappropriate stimulation of sec hair cells by sequestered otoconia in response to changes in head position concerning gravity.
• There are two pathological mechanisms- the theory of cupulolithiasis and the theory of canalolithiasis.
• Otoconia are calcium carbonate crystals normally embedded in the gelatinous otolithic membranes of the utricle and saccule.

• Canalolithiasis: Free floating otoconia find their way into the duct of the semicircular canal.
• Cupulolithiasis: Otoconia attach themselves to the cupula of a semi-circular canal.
• Changes in head position in the plane of that SCC will result in displacement of the cupula, either directly in the case of cupulolithiasis or indirectly by altering endolymphatic fluid pressure in the case of canalolithiasis.
• The cupular displacement results In vertigo and nystagmus in the plane of the stimulated SCC.

The vestibulo-ocular reflex (VOR) pathway

• The vestibular pathway has impulses going on from the 3 canals, the utricle and the saccule. The impulses from the superior canal, lateral canal, and utricle are carried via the superior vestibular nerve. The impulses coming from the posterior nerve and the saccule are carried by the inferior vestibular nerve. Both these nerves fuse to give signals to the common vestibular nerve, from where the impulses go to the vestibular nucleus. From the vestibular nucleus,3 efferents come. First, towards the medial longitudinal fascicular, the second efferent is towards the spinal cord, and the third is towards the cerebellum.
• From the medial longitudinal fascicular, the impulses go towards the nucleus of the 3^rd, 4^th, and 6^th nerves. These 3 nerves are responsible for supplying the extraocular muscles of the eye. Stimulation of these extraocular muscles results in the movement of the eye, called the nystagmus.
• The direction of the nystagmus is dependent on which canal and which side is stimulated. There is efferent activity on one side and inhibitory activity on the other side.
• If the posterior or the superior canals are stimulated, there is vertical and torsional nystagmus. Horizontal canal stimulation shows horizontal nystagmus.
• A vestibular activation causes an ocular reflex. Therefore, this pathway is called the vestibule-ocular reflex.
• In cases where the otoconia is in the posterior or anterior SCC, the nystagmus will be vertical-torsional.
• In contrast, the nystagmus will be horizontal in cases where the otoconia are in the lateral SCC.
• The most common canal to be affected in the BPPV is the posterior canal > horizontal canal > superior canal

Epidemiology Of Benign Paroxysmal Positional Vertigo (BPPV)

• Women are more frequently affected than men.
• Most common in the elderly.
• The majority of patients have posterior SCC BPPV, while about 15% have the lateral SCC variant. The anterior (superior) SCC variant is rare.

History Of Benign Paroxysmal Positional Vertigo (BPPV)

• Patients with BPPV experience severe vertigo (room-spinning sensation) associated with changes in head position.
• The most frequently cited occurrence of this symptom follows rolling over or getting into bed and assuming a supine position.
• Frequently, a specific side is identified as being associated with the onset of symptoms.
• The patient will also experience similar symptoms arising from the bending position, such as looking up to take an object off a shelf, tilting the head back to shave, positioning the head in the hairdresser’s chair, or turning rapidly.
• Symptoms occur suddenly and last on the order of seconds but never over a minute.
• Episodes of vertigo frequently are clustered in time and separated by remission lasting months or more.
• The patient may also report that periods of active disease are associated with constant feelings of lightheadedness worsened by head movement. These chronic balance problems may be worse on awakening. 
• There are no concomitant auditory symptoms such as hearing loss and/or tinnitus.

Predisposing Factors To Benign Paroxysmal Positional Vertigo (BPPV)

• When the BPPV is idiopathic and has no identified cause, it is called the primary BPPV.
• Secondary BPPV is a condition that happens secondary to any of the following.
  • Closed head injury
  • Vestibular neuritis
  • Infections
  • Surgical procedures, including stapedectomy
  • Insertion of a cochlear implant
  • Prolonged bed rest
  • Meniere’s disease
• Amongst secondary BPPV, closed head injury cause is the most common predisposing factor.

Treatment Of Benign Paroxysmal Positional Vertigo (BPPV) - Dix Hall Pike Maneuver

• To perform a provocative Dix-Hallpike maneuver, the patient’s head is turned to the right, and the patient is quickly pitched backward (in the plane of the posterior SCC) until the head hangs over the end of the bed.
• It is the diagnostic investigation of choice for diagnosing BBPV.
• We put the patient in the position that provokes the BPPV. In this position, the midpoint of the posterior SCC duct is lowermost, and any otoconia in the duct will, therefore, move away from the ampulla and come to rest at the midpoint of the duct.
• As the otoconia move away from the ampulla, they create a negative fluid pressure and thereby produce an excitatory ampullofugal deflection of the cupula.
• The clinician will observe vertical torsional nystagmus after a latent period of several seconds, with the quick phases directed upwards and towards the lowermost (affected) ear.
• With a gaze toward the lowermost ear, the nystagmus will appear to be predominantly torsional, whereas, with a gaze towards the uppermost ear, it will appear to be predominantly vertical.
• The nystagmus typically lasts for less than 30 seconds and is associated with intense vertigo.
• Nystagmus- characterization and types
  • RT/LT, vertical/horizontal, changing
  • Torsional=rational-clockwise/ counter-clockwise
  • Geotropic- towards the earth
  • Ageotropic- opposite.
• The pattern of response consists of the following-
  • Nystagmus is a combined vertical up-beating and rotary (torsional) component beating towards the downward eye (the superior poles of the eye beat towards the downward ear). Pure vertical nystagmus is not BPPV.
  • Latency of onset of nystagmus (seconds) is common.
  • The duration of nystagmus is short (< 1 minute).
  • Vertiginous symptoms are invariably associated.
  • The nystagmus disappears with repeated testing (i.e., it is fatigable).
  • Symptoms often recur with the nystagmus in the opposite direction when the head returns to the upright position.

Also Read: Acoustic Neuroma: Classification, Causes, Clinical Features, Symptoms

Epley's Repositioning Maneuver

• The patient is sat on the table with the head turned 45° to the affected (right) side.
• Brought down rapidly with the head turned by 45° to the affected (right) side and extended over the edge of the table with the neck well supported.
• The head is then turned 90° to the opposite (left) side.
• Rotate the head and body 90° facing downwards (135° from the supine position).
• The patient is next brought to the sitting position with the head turned forward.
• Contraindications Of Epley's Repositioning Maneuver
  • Severe neck disease, the best solution in this situation is to carry out an Epley’s maneuver on a couch where the upper half of the body can be lowered by 20-30°, which obviates the need for head reclination.
  • Severe carotid stenosis.
• Post-treatment patients should be instructed
  • To remain upright for 24 hours after the treatment
  • To avoid sleeping on the affected side for the following week.
  • To avoid sudden head movements.

Also Read: Middle Ear Implant : Transducer, Vibroplasty

Forced Prolonged Position on the Healthy Side 

• Vannuchi et al. advised patients with h-BPPV to lie down on the healthy side for 12 hours, maintaining the affected h-SCC uppermost, to allow the otolithic debris to gravitate to the vestibule.
• They reported total recovery within 3 days in 74.3% of 35 treated patients.
• Cases in which h-BPPV converted to ipsilateral p-BPPV were successfully treated using Semont’s maneuver.
• However, the presence of obesity and cervical spondylosis did not permit maintenance of the position for the time required.

Hope you found this blog helpful for your ENT Residency Otology Preparation. For more informative and interesting posts like these, keep reading PrepLadder’s blogs. 

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